InPlant—Machine Enclosure Manufacturers. Custom prefabrication of Modular Wall Partitions or Modular Machine Room, assembled using a Modular Building System that provides safe and economical ways to protect your personnel & equipment. Your interior Partition Walls and Machine Room Partitions are designed with a non-progressive system built for change and growth. The Modular Building System allows flexibility to expand, reconfigure, and relocate your structure — for lower future spending and maximum return on your investment.